1. Field of the Invention
The present invention relates to a coating apparatus, a coating method, and a method for manufacturing an optical film, and in particular to a technology to suppress vibration of a coating apparatus.
2. Description of the Related Art
Apparatuses of a type which uses a die coater (slot die) for discharging a coating solution from a manifold via a slot have been widely used as a coating apparatus for coating a surface of a web (supporting medium) with a coating film (thin film) having a desired thickness. Such a die coater has several types including a slide coater, a fountain coater, and an extrusion coater, and an appropriate type of die coater depending on an application is used to form a film (coating film) such as a high quality optical film.
In such coating apparatuses, a coating section and a web are usually fixedly mounted to a vibration resistant base so that vibration exerted on the coating section and the web can be suppressed.
In order to form a coating film having high quality by a coating apparatus which is precision measuring equipment, it is preferred to suppress vibration of the coating apparatus as much as possible so as to prevent vibration that may lead a poor surface profile of a coating film such as stepped unevenness; however, there has not been found any document so far that discloses or suggests a specific base structure for effectively suppressing vibration exerted on a coating apparatus.
The present invention has been contrived in view of the above situation, and one object of the present invention is to provide a coating apparatus which includes a base for effectively suppressing vibration, a coating method for effectively suppressing vibration, and a method of manufacturing of an optical film, such as a coating film which is obtained by using the coating apparatus or the coating method.